As E varies among elliptic curves defined over the rational numbers, a  theorem of Bhargava and Shankar shows that the average rank of the  Mordell-Weil group 
 is bounded.  If we now fix a Galois number field  K, how does the Mordell-Weil group E(K) behave on average as a Galois  module? We will report on progress on this question, which is obtained by  instead studying the associated p-Selmer groups of E/K as Galois modules.
We construct some novel Selmer groups which describe certain invariants of  these modules, and go on to study the behaviour of these new Selmer groups. This in turn allows us to give bounds for certain behaviour for the  Mordell-Weil groups.